JPH0585358A - Vehicular wheel set steering gear - Google Patents

Abstract

PURPOSE:To provide a vehicular wheel set steering gear desirable especially in linear high-speed travel performance. CONSTITUTION:A front wheel set 1 and a rear wheel set 2 are respectively connected by parallel links (N-links) 13, 14, and the lateral direction between the N-links is connected by an elastic body 17. The N-links 13, 14 are provided with such a structure as to be rotatable around the pins 18, 19 of connecting parts between the wheel sets and N-links and the pins 15, 16 of connecting parts between truck beams and the N-links. The improvement of linear high- speed travel performance can be thereby expected without having adverse effect on curve turning performance so as to provide a high speed vehicle having desirable effect on the high speed travel in all line areas such as a linear road and a curved road.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle wheel shaft steering device, and more particularly to a vehicle wheel shaft steering device having improved running stability during straight high speed running.

[0002]

2. Description of the Related Art Bogies widely used in high-speed vehicles at present are supported by a wheel axle support axle box and a bogie frame by horizontal leaf springs having rubber inserted at both ends thereof, so that the leaf springs are rigid in the front-rear and left-right directions. It is elastically connected to the bogie frame by utilizing it. The vehicle body is supported by side bearings. Generally, the rigidity of the horizontal leaf spring is high, and excessive lateral pressure acts on the wheel flange when passing through a curve, so that the flange wear tends to be remarkable. If the horizontal leaf springs have soft support rigidity in the front-rear direction (carriage traveling direction) to improve the turning performance of the bogie when passing a curve, the curve passing performance is slightly improved, but the straight running performance of the vehicle is reduced. . That is, the straight running performance and the curve passing performance conflict with each other. Therefore, in order to improve the curve passing performance, in order to make the yawing motions of the front and rear wheel shafts in opposite phases, they are connected by a Z-shaped parallel link (provisionally called Z link) mechanism to improve the straight running performance. There is a new mechanism that makes it easier to maintain and easily pass through curves (patent publication, Sho
51-14772).

[0003]

However, it is theoretically clarified that the structure described above has a very good curve passing performance at high speed running, but the stability of body snake action is slightly lowered at straight running (Yokose). , And 3 others, the Japan Society of Mechanical Engineers, 56-528 (1990-8), 2140), which qualitatively agreed with the test results of the actual prototype vehicle.

At the time of running a vehicle, it is one of the important issues to achieve both good passing performance on a curve and improvement of straight running performance.

It is an object of the present invention to provide a vehicle wheel axle steering system capable of maintaining stable performance even in a straight high speed range.

[0006]

The above object is to connect the front wheel shaft and the rear wheel shaft by independent parallel links (tentatively referred to as N-links) so that the rear wheel shaft and the front wheel shaft also move during lateral movement of the front wheel shaft. This is achieved by making them move laterally in phase.

[0007]

[Action] In order to improve the running performance and safety of railway vehicles, it is necessary to prevent the snake action (self-excited vibration) that occurs particularly in the high speed range and the forced snake action (forced vibration) due to track deviation. is there.

The serpentine behavior in a railroad vehicle is a geometrical one determined by the shape of the tread surface of the wheel and the shape of the rail, and the wheel. There is a kinetic phenomenon that occurs via the creep force at the contact point of the rail. In each of these, the lateral movement of the wheel axle (or bogie) and the turning movement about the vertical axis are coupled to each other, and once they occur, the amplitude of the vibration exponentially increases and then attenuates again. It is a dangerous thing. Therefore, first of all, the basic properties of the snake behavior of the elastically supported axle alone are examined by characteristic roots. In general, it is composed of two negative real roots with extremely large absolute values and a set of conjugate complex roots. It is this conjugate complex root that controls the snake's action, and its real part gives a negative value and stable oscillation in the low speed range, but as it enters the high speed range, the absolute value gradually decreases and finally becomes a positive value and becomes unstable. Vibration. By the way, if the lateral motion of the wheel axle and the rotational motion about the vertical axis (yawing) are not coupled and independent of each other, the absolute value of the real part of the conjugate complex root in ordinary railcars will be extremely large. Therefore, the conjugate complex root can be regarded as a negative real root. In other words, even if the wheelset is biased from the center position for some reason, it returns to the center position in a non-vibrating manner. Therefore, in order to improve the stability of the snake action, it is necessary to minimize the coupling between the lateral movement of the wheel axle and yawing.

Further, the twin-axle carriage handled in the present invention will be considered. In the bogie, there are a characteristic root in which the yaw motions of the front and rear wheel shafts vibrate in opposite phases, and a root in which the left and right movements of the front and rear wheel shafts vibrate in the same phase. Generally, the limit speed of the antiphase one is lower than that of the inphase one. In order to increase the limit speed of the antiphase wheel, connect the front and rear wheel axles with a Z-shaped link, and make the ratio of the angular amplitudes of the front and rear wheel axles asymmetrical (so that the rear wheel axle has a large angular amplitude relative to the front wheel axle). If you control it, you can increase the limit speed of snake action (Yokose and 3 others, Proceedings of the Japan Society of Mechanical Engineers, 56-578 (1990-3), 21.
40).

Next, if the phase difference due to the lateral movement of the front wheel shaft and the rear wheel shaft is made small, yawing of the carriage is unlikely to occur. For that purpose, the front wheel shaft and the rear wheel shaft are connected by independent parallel links (tentatively referred to as N links), and the wheel shaft and the parallel link are connected by a center pin whose connecting point is located at the wheel shaft center position. Also, the parallel links are connected to the bogie beams provided on the bogie frame by central pins, and the parallel links are connected to each other with an elastic body. Therefore, if the rear wheel shaft is moved laterally in the same phase as the front wheel shaft during the lateral movement of the front wheel shaft, yawing of the carriage is less likely to occur. That is, the coupling effect between the lateral movement of the bogie and the yawing movement is reduced, and the limit speed (vehicle speed at the boundary at which the snake movement moves from stable to unstable or from unstable to stable) increases.

Although the railcar has been described above, in the case of a four-wheeled vehicle, unstable vibration called shimmy occurs in a high speed region. Shimmy is also a phenomenon similar to the behavior of railroad vehicles, so it can be suppressed by applying the means of the present invention.

As described above, the present invention was devised on the basis of the kinematic characteristics of railway vehicles.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view when the present invention is applied to a truck having a Z-link. In the figure, 1 is a front wheel axle,
2 is a rear wheel axle, 3 is an axle box, 4 is a bogie frame, 5 and 6 are bogie beams,
7 is rubber at the bolster anchor mounting position, 8 is side bearing, 9
Is a lateral support spring of the wheel axle, 10 is a longitudinal support spring of the wheel axle, 11 is a Z link device, 12 is rubber of a Z link attachment portion, 13 and 14 are parallel links (N links), 1
Reference numerals 5 and 16 are connecting pins of the bogie beam and the N-link, 17 is an connecting spring of the N-link, and 18 and 19 are connecting pins of the front wheel shaft and the rear wheel shaft and the N-link. These connecting pins are shown in the drawings. Each axle is mounted via a bearing (for example, a spherical bearing) attached to an unloaded axle.

As described above, according to the present invention, the front wheel shaft 1 and the rear wheel shaft 2 are connected by the parallel links (N links) 13 and 14, respectively, and the left and right directions between the N links are connected by the elastic body 17. To be done. Furthermore, for lateral movements of the wheel sets 1 and 2, the N-links 13 and 14 move around the pins 18, 19 with respect to the wheel sets with respect to the bogie beams 5, 6 to the pin 15,
It has a structure capable of rotating around 16.

Next, the operation of the present invention having the above configuration will be described.

Assuming that the wheel shaft 1 moves laterally (upward in the plane of the drawing), the connecting point 18 between the wheel shaft 1 and the parallel link 13 is formed.
(If necessary, insert an elastic body into the joint between the parallel link 13 and the wheel axle) moves laterally,
Swivels clockwise around the mounting pin 15.
As a result, the elastic body 17 inserted between the parallel links is compressed, and the parallel link 14 coupled to the rear wheel shaft pivots counterclockwise about the mounting pin 16. By this turning, the attachment point 19 of the rear wheel shaft and the parallel link moves laterally (upward on the paper surface). As a result, the left and right movements of the front and rear wheel shafts are in phase. For this reason, as described above, the coupling effect of the yawing motion and the lateral motion of the carriage is reduced, and the serpentine action is less likely to occur.

FIG. 2 is a plan view of another embodiment in which the present invention is applied to a truck having a Z-link. The same parts as those in FIG. 1 are designated by the same reference numerals. The difference from FIG. 1 is that the front wheel shaft 1 and the rear wheel shaft 2 and the connecting pin 1 of the N links 13 and 14 are connected.
8 and 19 are attached on E-shaped beams 20 and 21 attached to the left and right axle boxes. By doing so, the present invention can be applied to a trolley in which a bearing (for example, a spherical bearing) is not attached to the center of the wheel axle. In short, pin 1
It suffices that 8 and 19 are provided at the center positions of the respective wheel axles so that the N-links are not displaced when the wheel axles rotate around a vertical axis passing through the center. It is clear that the present embodiment also operates in the same manner as in FIG. 1, and therefore the description of the operation will be omitted.

In order to understand the effects of the present invention in detail, an example of calculation results for a high-speed bogie (bullet train) is shown in FIG. The abscissa is the front and rear support rigidity of the wheel axle kW.
X and the ordinate represent the limit speed v of the serpentine action, and the conventional Z-link bogie (shown by a broken line) and the ZN link bogie of the present invention (a Z-link and N-link combined bogie, shown by a solid line). It is a comparison of the speed limit with. The snake behavior is stable at a speed equal to or lower than the limit speed V, but becomes unstable at a speed equal to or higher than V, and the vehicle vibration diverges. Therefore, the higher the limit speed, the better the stability of snake action.

Further, the positions of the N-link mounting pins with respect to the front wheel shaft and the rear wheel shaft are changed to appropriately adjust the lateral steering ratio of the front and rear wheel shafts (in this case, the N-link mounting position is asymmetric with respect to the traveling direction of the carriage). By choosing
If the rigidity of the elastic body of the link connection is made appropriate, the critical speed of snake action can be further increased.

As described above, in the Z-N-linked steering bogie, the N-link device acts to improve the stability of straight running and the Z-link device acts to improve the curve passing performance. It is possible to sufficiently eliminate the drawbacks, and it is expected that a significant speed increase will be expected for future high-speed trucks.

Although the embodiment in which the present invention is applied to the truck having the Z-link mechanism has been described above, the present invention is also effective when applied to a normal truck (the Z-link is omitted from FIG. 1). Have. That is, in order to facilitate the passage of a curved line in a normal bogie and to reduce the wheel lateral pressure and the wheel flange wear, the rigidity of the wheel axle front-rear direction support spring 10 should be made small and the slope of the wheel tread should be made large. Good. However, if such soft support rigidity is used, the high-speed running performance on a straight line is deteriorated. However, if an N-link as shown in FIG. 1 is provided, as described in detail in the section (action), the limit of the serpentine action on a straight road is reduced. You can increase the speed.

Although the embodiment applied to the railway vehicle has been described above, the present invention can be extendedly applied to other transportation means such as a four-wheeled vehicle.

[0023]

As is clear from the above description,
According to the present invention, by means of an extremely simple structure,
It is possible to provide a vehicle wheel shaft steering device having good straight running performance.

[Brief description of drawings]

FIG. 1 is a plan view of a bogie of an embodiment in which the present invention is applied to a bogie with a Z-link.

FIG. 2 is a plan view of a bogie of another embodiment in which the present invention is applied to a bogie with a Z-link.

FIG. 3 is a diagram showing a result of theoretical calculation of a limit speed of a bogie to which the present invention is applied, with respect to a front-rear support rigidity KWX of an axle box.

[Explanation of symbols]

1 ... front wheel axle, 2 ... rear wheel axle, 3 ... axle box, 4 ... bogie frame, 5,
6 ... Bogie beam, 7 ... Elastic body, 8 ... Side support, 9 ... Lateral support spring for wheel axle, 10 ... Support spring for front and rear direction of wheel axle, 11 ...
Z-link device, 12 ... Elastic body, 13, 14 ... Parallel links (N-link), 15, 16 ... N-link joint pin of bogie beam, 17 ... N-link joint elastic body, 18, 19 ... Wheel axle and N Pins connected to the link, 20, 21 ... E-shaped beam.

Claims (3)

[Claims] 1. A displacement mechanism comprising a front wheel shaft and a rear wheel shaft having wheels at both ends thereof, wherein one of the front wheel shaft and the rear wheel shaft is displaced in the wheel shaft direction with respect to the other wheel shaft in the same phase. A wheel axle steering device for a vehicle, comprising: 2. A front wheel shaft and a rear wheel shaft are respectively connected by parallel links, and the left and right directions between these parallel links are connected by an elastic body, and each parallel link is connected to each wheel shaft by a connecting pin and a bogie frame. A wheel axle steering device for a vehicle, wherein the wheel axle steering device is configured to be rotatable around a coupling pin of the vehicle. 3. The vehicle wheel axle steering system according to claim 2, wherein the front wheel axle and the rear wheel axle are used together with a Z link 11 which is connected by a Z-shaped parallel link.